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this video illustrates the efforts of a

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team of visualization and civil

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engineering researchers towards

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producing a high fidelity visualization

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of the September 11 2001 attack on the

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World Trade Center the visualization had

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to be eloquent to the non expert user

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the simulation was placed into context

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by modeling and importing the buildings

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of the WTC Plaza shown here color into a

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Google Earth model of lower Manhattan a

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finite element analysis simulation of

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the impact between the Boeing 767 and

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the top 20 floors of the North Tower was

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completed using a state-of-the-art

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simulation code then the simulation

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result were imported into a

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state-of-the-art animation system where

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the visualization was produced the

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simulation track the impact over

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three-quarters of a second real-time

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this sequence is 13 times slower than

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real-time all the animated geometry seen

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here was created automatically from the

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you

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this sequence visualizes the aircraft

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trajectory between the facade and the

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notice the oscillation of the ceiling

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this reverse angle shot visualizes the

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important damage sustained by some of

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the core colors using a camera with a

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distant header plane this sequence

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simultaneously visualizes the two floors

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notice the right engine titanium shaft

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which traverses the building virtually

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plane debris re-emerges on the office

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you

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the jet fuel in the central and two wing

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tanks was simulated using smoothest

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particle hydrodynamics or SPH nearby

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fuel particles were lumped together in

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the animation system and the fuel was

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rendered with reflections and

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refractions using a ray trace material

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notice how the wing tank fuel disperses

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first as the wings are considerably

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the core volumes are essential to the

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structural integrity of the building

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this sequence visualizes the damage the

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core columns and - they're connecting

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horizontal beams by rendering all other

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here are the core columns exclusively

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these sequences also turn out to provide

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a good visualization of the overall

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deformation of the aircraft as it enters

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the simulation did not consider the

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effects of the explosion and of the

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ensuing fire here the fuel particles

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were used in the animation system to

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automatically produce a plausible fire

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visualization as can be seen in this

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side-by-side visualization the

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simulation fuel particles control the

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elements that undergo it assists stress

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are eliminated from the computation by

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the FEI a simulation code is eroding

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elements correspond to entities that

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disintegrate such as a slab of concrete

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turning into dust although they do not

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have much relevance from the simulation

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standpoint eroded elements are important

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for the visualization eroded elements

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are using the animation system to

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automatically create and control visual

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produced leverages the strengths of a

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state-of-the-art simulation system which

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models the interactions in detail based

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on physics first-order principles and of

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a state-of-the-art animation system

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which produces a high-quality ization of

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the simulation results this was made

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possible by developing a scalable

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translator that automatically converts

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the simulation output data into an

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animation see the translator is general